Electric switch.



No. 705,!37. Patented July 22, 1902.

W. B. POTTER.

ELECTRIC SWITCH.

(Application filed July 27, 1900. Renewed Apr. 23, 1902.)

(No Model.)

(invent/or Wil h' amBPoULer union.

UNITED STATES PATENT "WILLIAM B. POTTER, OF SOHENEOTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEl/V YORK.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 705,137, dated July 22, 1902.

Application filed July 27, 1900. Renewed April 231 1902. Serial No. 104,321. (No model.)

To @ZZ whom it may concern; tember 7, 1897. However, the switch, includ- Be it known that I, WILLIAM B. POTTER, a ing the improvements set forth hereinafter, is citizen of the United States, residing at Schenadapted for various uses. ectady, in the county of Schenectady and In Fig.1, B is a box provided with a cover 5 State of New York, have invented certain O of magnetic material, secured thereto by a new and useful Improvements in Electric suitable screw 1. Inside the box is a coil A, Switches, (Docket No. 1,783,) of which the which may be supplied with current from following is a specification. the same source as'that flowing through the This invention relates to electric switches. switch,ornot, as desired. The boxBis secured IO The invention consists in means for sepato an insulating-base D by one or more screws rating switch-contacts which may be stuck To the lower side of the base D are setogether owing to arcing. In many typeset cured the terminals E E, 850., by the screws electric switches and in switches used on cer 3. A movable magnetportion or plunger G is tain circuits the contacts are liable not only mounted within the box for verticalmovement 15 to be impaired by arcing, but may be caused and is normally maintained by gravity in the thereby to be partially welded or stuck toposition shown. -The movable switch portion gether, so that they can be opened with great comprises a support H, of resilient material, difficulty. Thisisespecially true of switches provided with radial arms and mounted on for electric railways having sectional servicethe lower end of the plunger G, and on this 20 conductors, which switches are adapted to support, mounted in clips 71. h, &c., the caropcn automatically by gravity when their bon switch-contacts J J, &c. Then the coil actuating magnet-coils are open-circuited," A is energized, the plunger G is raised until whereby their opening is attended with great its upper portion engages in the recess 0 in uncertainty. Even in the case of the present a portion of the cap O, which extends down- 25 switch, although it has been constructed so Wardly into the center of the coil, and the that the liability of the occurrence of serious carbon contacts J, &c., are brought into conarcing is greatly decreased, it is highly detact with the terminals E, &c. The support sirable to guard against the possibility that H yields in this operation to prevent damagthe switch-contacts may be stuck together ing impact of the carbon contacts and by its 30 from this cause. The reason that it is so resiliency serves to hold the contacts tightly very important that the switch be opened in together and to compensate for any wear of the particular case of its use in a sectional the upper portion of the plunger G, which is railway is that if it should remain closed the of soft material, as will be seen hereinafter. surface contacts of the railway would remain A suitablymounted magnet N is provided 35 alive after the car had passed from above with extended pole-pieces O, adjacent to the them, so that the very advantage intended terminals E, in order to blow out the arc when to be obtained from the sectional safety systhe contact J is separated from the terminal. tem would not be had. The switch may be connected, as shown in Figure l is a vertical section of a switch thecircuits of Fig. 3, wherein Z is a surface- 0 embodying the invention. Fig. 2 is a plan contact or surface-rail section adapted to be of a detail thereof, and Fig. 3 is a diagramengaged by a collector carried by the car and matic illustration of circuit connections in connected with the coil A. R and T are also which such a switch might be used. surface contacts or rail sect-ions, which are This switch in general construction is simiadapted to be engaged by a second car-col- 45 lar to that disclosed in my application for lector independent of the first and are conpatent, Serial No. 654,793, filed October 11, nected with the switch to supply current to 1897, and is particularly adapted for use in the car-motors. The coilA is connected to a surface-contact railway, such as that deground and is adapted to be connected in sescribed in my Patent No. 589,786, dated Seprice with the motor through the contact Z and the collector. Blow-out magnet N is con nected in series between the switch and the main W by the connections N and N Recurring to Fig. 1, it will be seen that coil A is wound around a support V of insulating material. Surrounding the support V is a closed conductor U, which is adapted to prevent sparking at the surface contact Z of Fig. 3.

The improvements which it is desired to particularly point out herein may be described as follows: A sleeve F, of non-magnetic material, is mounted in the box B, so that an opening is provided in the bottom of the box. The sleeve is prevented from rotation by a pin X, which engages in the lower part of the box. The plunger G extends through the sleeve F and the opening in the base D and is provided with a shoulder I, which is adapted to rest on the top of the sleeve F to limit the downward movement of the core. A pin Q, mounted in the plunger, reciprocates in a vertical slot S in the sleeve to prevent the plunger from rotation. A thin cap Y, of non magnetic material, such as copper, is attached to the upper portion of the plunger and is adapted to fit the recess 0 of the cap 0. This cap and the sleeve F being of non-magnetic material serve to prevent the plunger from being held by residual magnetism in its closed position after the coil A has been open-circuited. The lower portion of the plunger is provided with a shoulder K and a reduced portion L, which portion is provided with one flat surface 4:. The supportH is provided with a hole of the same shape as the portion L, so that the latter may fit and reciprocate therein, but cannot rotate. A nut M serves to retain the support H on the portion L; but the support is not secured against the shoulder K, being permitted to have considerable play between the shoulder and the nut.

The operation is as follows: It may be assumed that arcing between the terminals E E and the contacts J, J, and J has caused them to stick together. Then when the coil A is open-circuited the plunger G is prevented by the non-magnetic cap Y and sleeve F from stickinginits raised position and falls bygravity until the shoulder K impinges upon the support H, and as the plunger is of considerable mass and the support H is made of resilient material the carbon contacts J J, 850., will be drawn a short distance across the terminals E E and forced downward away from the terminals, thus breaking any mechanical connection between the contacts and the terminals and opening the switch. In case the support H were made of rigid material the plunger G would force it directly downward, and, in fact, this would usually be the case unless the parts were especially designed. The plunger will not deliver a blow to the support I-I if the contacts are not stuck together, for the support will fall with the plunger as soon as the coil A is opcn-circuited. Hence the support is subjected to the blow only in case the contacts are stuck together.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of an actuator therefor, having a lost-motion connection therewith, whereby in opening the switch the actuator can have a free movement at first, and will then, if the contacts are stuck together, impinge against the switch portion to positively force the switch-contacts apart, against their tendency to stick.

2. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of an actuator therefor, having a lost-motion connection therewith, and non-mechanical means for moving the switch portion and holding itin the position to which it may have been moved, to close the switch and maintain it closed, whereby when said means is made inoperative the actuator can have a free movement at first, and will then, in case they cohere, impinge against the switch portion to positively force the switch-contacts apart.

3. In an electric switch, the contacts of which are liable to cohere, owing to arcing, the combination with the movable switch portion, of an actuator therefor, having a lostmotion connection therewith, said actuator being normally maintained by gravity in a position to maintain the switch open, and means for lifting the actuator and switch portion and holding them in their raised position, to close the switch and maintain it closed, whereby, when said meansis rendered inoperative, the actuator can move by gravity freely at first, and will then, if the contacts adhere, one to the other, impinge against the switch portion to positively open the switch.

4. In an electric switch, the contacts of which are liable to adhere, owing to arcing, the combination with the movable switch portion, of an electromagnet for moving the switch portion to close the switch, the movable portion of the magnet having a lost-motion connection with said movable switch portion, whereby, when the magnet-coil is opencircuited, the movable magnet portion can have a free movement at first, and will then, if one contact adheres to the other, impinge against the movable switch portion to open the switch, by forcing the contacts apart.

5. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, normally maintained in its open position by gravity, of an electromagnet for lifting said portion to close the switch, the movable portion of the magnet having a lost-motion connection with the switch portion, whereby, when the magnet-coil is open-circuited, the movable magnet portion moves freely by IIO gravity at first, and then, if the switch-contacts are stuck together, impinges against the movable switch portion to positively separate the contacts.

6. In an electric switch, the contacts of which are liable to be caused to cohere by arcing, the combination with the movable switch portion, of an electromagnet, the movable portion of which has a lost-motion con nection with the switch portion, said magnet portion and switch portion being normally maintained by gravity in a position to maintain the switch open when the magnet-coil circuit is open, and non-magnetic material between the movable magnet portion and the other parts of the magnet, to prevent sticking of the movable magnet portion in its raised position after the magnet-coil is opencircuited, whereby it is certain that the movable magnet portion will descend by gravity, freely at first, owing to the lost-motion connection, and will then, in case the contacts are sticking, impinge upon the movable switch portion to positively separate the switch-contacts.

7. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of an actuator therefor having a lost-motion connection therewith in the direction of motion of the actuator, the switch portion being immovable except in the direction of the motion of the actuator.

8. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of an electromagnet, the movable portion of which has a lost-motion connection with the switch portion, the switch portion being immovable except in the direction of motion of the movable magnet portion, whereby, when the magnet-coil is open-circuited, the movable portion of the magnet can have a free movement at first, and will then, if the contacts stick, impinge against the movable switch portion to open the switch.

9. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of an electromagnet, the movable portion of which has a lost-motion connection with the switch portion, the switch portion being immovable except in the direction of motion of the movable magnet portion, and means for preventing any movement of the latter eX- ceptback and forth in the path through which it is drawn by its coil, whereby, when the magnet-coil is open-circuited, the movable portion of the magnet can have a free movement at first, and will then, in case the contacts are stuck together, impinge against the movable switch portion to open the switch.

10. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with a movable switch portion made of resilient material, the resiliency of which prevents severe impact in closing, of

an electromagnet, the movable portion of which has a lost-motion connection with the switch portion, whereby, when the magnetcoil is open-circuited, the movable magnet portion can have a free movement at first, and will then, if the contacts are stuck together, impinge against the resilient switch portion, to exert upon the sticking contacts strains both parallel and transverse to the direction of motion of the movable magnet portion.

11. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the line-terminals, of carbon switch-contacts, aresilient support therefor which yields in closing to prevent injury to the carbons, a support for the carbon contacts, and an electromagnet, the movable portion of which has a lost-motion connection with the support, whereby, when the magnetcoil is open-circuited, the movable magnet portion can have a free movement at first, and will then impinge against the resilient switch portion to force the carbons across and away from the surfaces of the line-terminals.

12. The combination with an electric switch, thecontacts of which are liable to be caused by arcing to be stuck together, of means for opening the switch whereby, in case the contacts are stuck together, a hammer-blow is automatically delivered to separate them, but no blow is delivered in case the contacts are not stuck together.

13. The combination with an electric switch, of an electromagnet for closing the same, and a mass of magnetic material which falls by gravity against the switch when the magnetcoil is open-circuited, to force the switch open.

14. The combination with an electric switch, the contacts of which are liable to be caused by arcing to be stuck together, of an electromagnet for closing the same, and a magnetic hammer which falls by gravity when the magnet coil is open-circuited, and impinges upon the switch to open the same, only in case the switch is held closed by the coherence of the contacts.

15. The combination with an electric switch, the contacts of which are liable to be caused by arcing to be stuck together, of an electromagnetic hammer which falls by gravity, and impinges upon the switch to open the same when the magnet-coil is open-circuited, and a stop-rest for the hammer which permits the hammer to fall through and below the space occupied by the switch in its closed position.

16. In an electric switch, the contacts of which are liable to be caused by arcing to be stuck together, the combination with the movable switch portion, of an electromagnet, the movable portion of which is provided with a shoulder, and means for holding the movable switch-piece so that it can move freely on the movable magnet portion below the shoulder, whereby, when the magnet-coil is opon-circnited, the magnet portion falls by &

gravity, and in case the contacts are stuck together, its shoulder impinges upon the switch portion, to open the switch, and means for limiting the fall of the movable magnet portion.

17. In an electric switch, the contacts of which are liable to be caused by arcing to be stucktogether,the combination with the movable switch portion, of an actuator therefor having a portion with a non-circular periphery, said switch portions fitting over said non-circular portion, to prevent rotation, and having a lost-motion connection with said actuator in the direction of motion of the latter, said actuator being normally maintained by gravity in a position to maintain the switch open, and means for lifting the actuator and switch portion and holding them in their raised position, to close the switch and maintain it closed, whereby, when said means is rendered inoperative, the actuator can gravitate freely at first, and will then, if the contacts are stuck together, impinge against the switch portion to positively open the switch.

18. In an electric switch, the contacts of which are liable to stick, owing to arcing, the combination with the movable switch portion, of means for delivering a hammer-blow thereto, to separate the sticking contacts, and an electromaguet for closing said switch and controlling said means, the latter being operative when the magnet-coil is open-circuited.

19. In an electric switch, the contacts of which are liable to stick together, owing to arcing, the combination with the movable switch portion normallyheld by gravity in its open position, of an electromagnet for raising the switch portion to close the switch, and means for delivering a hammer-blow to the movable switch portion when the magnetcoil is open-circuited.

20. In an electric switch, the contacts of which are liable to stick together, owing to arcing, the combination with the movable switch portion, of means for delivering a blow thereto to separate the contacts in case they are stuck together, and an electromagnet which controls said means and permits it to be operated when the magnet-coil is open-circuited, and the contacts are stuck together.

21. The combination with an electric switch, normally held in its open position by gravity, of means whereby, when the switch is closed, a hammer-blow is automatically, in case the contacts are stuck together, delivered to the switch to force it open. 

